Day 18: Grand Prismatic Spring

Close-up of one of the lava-like mineral-rich streams on the edge of Grand Prismatic Spring.

Grand Prismatic Spring in Yellowstone N.P. is the third largest hot spring on earth ( with water temperature of 160 ºC ) but considered the most fascinating one.

Algae and pigmented bacteria in the microbial mats that grow around the edges of the mineral-rich water spring change color dependent on the ratio of chlorophyll to carotenes produced by these organisms.

( image courtesy of )

This is definitely one of the sights you want to see in your lifetime.

Date: August 23rd, 2010.